[time-nuts] Modeling vs reality question re my TIC

Chris Albertson albertson.chris at gmail.com
Mon Mar 10 16:26:58 EDT 2014

On Mon, Mar 10, 2014 at 12:12 PM, Bob Stewart <bob at evoria.net> wrote:

> A range of 0.715V-2.38V is totally outside my expectations.  The only way I can get close to these values is if the internal CHOLD in the PIC is only a fraction of the 120pf they say it has - say 20pf.  Any thoughts would be appreciated.

Could it be a software issue?  20pf seems about right for a normal
input pin in a typical chip.  They all have diodes protecting from
static and 20 pf seems like what I'd expect.     You say there is an
internal 120 pf cap inside the PIC?  If so you'd need to connect that.
 It may be that you are not doing that correctly or at the time you
think you are.   I'm guessing and we'd need both the spec sheet and
your code to know for sure.

Chris Albertson
Redondo Beach, California

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